JPH0797615A - Continuous heat treatment equipment having crown changable roll - Google Patents

Abstract

PURPOSE:To stabilize the pass performance of a steel strip in the continuous heat treatment equipment and prevent the trouble by ejecting fluid for cooling from the inside of a roll, shell, controlling a temp. profile in the roll width direction and adjusting the roll crown. CONSTITUTION:Plural zones are formed in the width direction of the roll inside the roll shell and plural ejecting nozzles are arranged in each zone so as to direct the inner surface, and gas flow rate from the outer part is adjusted. By this constitution, the temp. profile in the width direction of the roll is adjusted and the crown shape of the roll can be changed so as to match the size, shape and material of the steel strip and heat cycle. Further, the troubles, such as defective shape, meandering, the development of contraction and defective quality of the steel strip, are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous heat treatment facility equipped with a crown variable roll.

[0002]

2. Description of the Related Art In continuous heat treatment equipment for continuously heat-treating steel sheets, the hearth rolls for conveying the steel strip are usually
A convex crown is used to stabilize the strip running of the steel strip. Further, as a method for controlling the crown amount of the hearth roll in the furnace, there is, for example, a technique disclosed in Japanese Patent Publication No. 58-43454, which is a steel plate in which a refrigerant is blown inside or outside the hearth roll in the furnace. The flow rate and temperature of the refrigerant are adjusted so that the amount of crown corresponds to the size.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of adopting the hearth roll to which the crown control method disclosed by Japanese Patent No. 43454 is applied and preventing the meandering and drawing of the steel sheet and performing stable striping, in all strip sizes and heat cycles, In order to obtain the optimum crown shape with good responsiveness, there has been a problem that the roll crown adjusting device becomes too complicated. That is, in order to change the crown shape with good responsiveness, it is realized by partially blowing the refrigerant in the roll width direction, but in order to make the refrigerant blowing portion variable according to the steel plate size, the blowing header is It is necessary to provide a means for dividing the steel sheet in the width direction and adjusting the amount of the refrigerant supplied to the divided compartments, which naturally causes a problem of making the apparatus complicated.

[0004]

The present invention has been made to solve the above-mentioned problems, and a plurality of zones are formed inside the roll shell in the roll width direction, and a plurality of jets are provided in each of the zones. A crown variable roll formed by providing a nozzle and arranging the injection nozzle so as to be directed to the inner surface of the shell, and changing the flow rate of the cooling gas from the outside of the roll to change the temperature profile in the roll width direction is continuous. The present invention provides a continuous heat treatment facility characterized by being provided in at least a part of the heat treatment facility. Further, in order to enhance the cooling effect, fins are provided inside the roll shell to facilitate the crown change. Also, the thickness of the roll shell is changed in the roll width direction for the same purpose of enhancing the cooling effect.

[0005]

1 (a) and 1 (b) show the sectional structure of a crown variable roll according to the present invention. In FIG. 1A, the roll 1 is rotatably supported by a bearing 2, and a cooling gas supply pipe 3 and a cooling gas discharge pipe 4 are rotatably supported by the roll by an internal bearing 2 '. The cooling gas supply pipe 3 and the cooling gas discharge pipe 4 have a double pipe structure, and the cooling gas supply pipe 3 is the cooling gas discharge pipe 4.
The structure is such that it can be moved in the axial direction of the roll by being guided by. The cooling gas 5 is introduced by the cooling gas supply pipe 3, and is supplied to the cooling gas branch pipes 7 and 8 by the tip seal head 6. The cooling gas branch pipes 7 and 8 are provided with gas injection holes to inject the cooling gas 5 toward the inner surface of the roll shell. At this time, the cooling gas branch pipes 7 and 8 are divided into regions for injecting gas in the roll width direction. To jet. When the width of the steel strip conveyed by the roll is in the region C, the temperature difference between the non-contact portion of the roll and the steel strip, the regions A and B, is cooled from the inside of the roll to thereby obtain the temperature difference between the contact portion C of the steel strip. Can be reduced, and the roll crown shape can be prevented from changing.

FIG. 1 (b) shows the case where the steel strip width changes to D. The cooling gas supply pipe 3 is moved in the direction E, and the tip seal head 6 connected to the cooling gas supply pipe 3 is also moved in the direction E. The cooling gas 5 supplied from the tip seal head is supplied to the cooling gas branch pipe 8 but not to the cooling gas branch pipe 7. Therefore,
Only the region B is cooled with respect to the steel strip width D. The gas injected into the roll is collected in the cooling gas discharge pipe 4 through the cooling gas discharge hole 9 and discharged to the outside of the roll.

The crown variable roll according to the present invention is installed inside a roll chamber provided in the upper and lower parts of the furnace, and the temperature of the roll chamber is controlled independently,
Further, the effect can be enhanced.

Further, as shown in FIG. 2, by providing the fin 10 inside the roll shell and injecting the cooling gas 5 toward the fin 10, the cooling effect of the variable crown roll can be further enhanced. FIG. 3 shows an example in which the thickness of the roll shell is changed in the width direction. The shell thickness t at the roll end is made smaller than the shell thickness t ₁ at the center. In the cooling gas 5 injection region G, since the shell thickness t is small, the heat capacity of the portion to be cooled is small.
By injecting, it becomes possible to cool to the target temperature in a short time. Therefore, in actual operation, when the width of the steel strip changes, the target temperature can be quickly obtained, and the crown can be changed quickly.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) and 1 (b) show a sectional structure of a crown variable roll according to the present invention. It is important to maximize the cooling effect by providing a plurality of cooling gas branch pipes 7 and 8 in the circumferential direction of the roll. Also, this figure shows
Although there are two regions divided in the width direction, it is possible to set the optimum number of regions in consideration of the size of the steel strip and the strip pattern.

The crown shape can be changed by measuring the temperature of the roll shell at a plurality of points with thermocouples embedded in the roll shell and cooling gas so that a preset temperature pattern is obtained based on the actual temperature at each point. 5, the tip seal head 6 and the cooling gas supply pipe 3 are moved in the roll width direction by the moving device 11 so that the cooling gas blowing area becomes the same as the calculated set value.

[0011]

According to the present invention, in the actual operation, according to the size, shape, material and heat cycle of the steel strip,
The shape of the roll crown can be changed, and troubles such as poor shape of the steel strip, meandering, drawing, and uneven quality are eliminated. Further, as the cooling fluid, it is possible to use steam, cooling water in addition to air, an inert gas such as nitrogen gas, hydrogen gas, etc. In particular, it is possible to cool at low cost by using air. Since it is possible, there is no increase in product cost.

[Brief description of drawings]

1A and 1B are sectional views showing a crown variable roll according to the present invention.

FIG. 2 is an enlarged view of a portion corresponding to a portion F in FIG. 1B, showing a structure in which fins are provided inside the roll shell.

FIG. 3 shows an example in which the shell thickness of the crown variable roll is changed in the width direction.

[Explanation of symbols]

 1 Roll 2 Bearing 2'Internal Bearing 3 Cooling Gas Supply Pipe 4 Cooling Gas Discharge Pipe 5 Cooling Gas 6 Tip Seal Head 7, 8 Cooling Gas Branch Pipe 9 Cooling Gas Discharge Hole 10 Fin 11 Moving Device 12 Steel Strip

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Matsuura 46-59 Nakahara, Tobata-ku, Kitakyushu, Fukuoka Prefecture Nippon Steel Co., Ltd. Machinery & Plant Division

Claims (3)

[Claims] 1. A plurality of zones are formed inside the roll shell in the roll width direction, a plurality of jet nozzles are provided in each of the zones, and the jet nozzles are arranged so as to be directed to the inner surface of the shell. A crown variable roll characterized in that at least a part of the continuous heat treatment equipment is provided with a crown variable roll formed so as to change the temperature profile in the roll width direction by changing the flow rate of the cooling gas from the outside. Continuous heat treatment equipment. 2. The continuous heat treatment equipment according to claim 1, wherein fins are provided inside the roll shell. 3. The continuous heat treatment equipment according to claim 1, wherein the shell thickness of the roll shell is changed in the roll width direction.